Alright, let's work through 8921994 times 64199866 step by step
8921994 × 64199866 = 64199866 × (8921994)
+ 64199866 × 4 that equals 256799464
+ 64199866 × 90 which equals 5777987940
+ 64199866 × 900 that is equal 57779879400
+ 64199866 × 1000 yielding 64199866000
+ 64199866 × 20000 that results in 1283997320000
+ 64199866 × 900000 which equals 57779879400000
+ 64199866 × 8000000 that equals 513598928000000

= 572790819252804
